This easy to make and delicious focaccia comes together all in one day using your already ripe sourdough starter. Top with tomatoes, olives, rosemary, and coarse sea salt—or, really, anything you have in the kitchen that's fresh and sounds delicious!
Mix the flours, water, salt, and ripe sourdough starter in a stand mixer on speed 1 for 1 to 2 minutes until incorporated.
Increase to speed 2 and mix for 5 minutes until the dough strengthens and clumps around the dough hook.
Let the dough rest in the mixing bowl for 10 minutes.
Turn the mixer to speed 1 and slowly drizzle in the olive oil while mixing.
Once the olive oil is absorbed, increase to speed 2 for 1 to 2 minutes until the dough comes back together.
Transfer the dough to a bulk fermentation container and cover.
Perform 4 sets of stretch and folds at 30-minute intervals, starting 30 minutes after the start of bulk fermentation.
Liberally oil the inside of a rectangular pan or two circular baking pans.
Gently scrape the dough out of the bulk fermentation container into the pan.
Proof the dough in the pan for 4 hours, stretching it to the edges every 30 minutes for the first hour.
Preheat your oven to 450°F (230°C) with an empty rack in the bottom third.
Dimple the top of the dough with wet fingers, drizzle with olive oil, and sprinkle with herbs and coarse sea salt.
Bake until golden on the top and bottom, about 30 minutes.
Let the focaccia cool in the pan, then transfer to a cooling rack.
Enjoy the focaccia warm from the oven, best on the day it's baked.